Mashable Invites is a place to swap invites for "Web 2.0" sites that are currently in private beta mode. Just add your name to an invites list and other Mashable Invites members will drop by and invite you.
An online calendar that claims: "natural language entry, ajax, full screen, blazing fast, invitations, sms reminders,
repeating events, integrated maps, tagging, share by tags, customizable, multiple themes, simple sharing, weather, track myspace, flickr,
webshots, livejournal, blogger and more, instant photo sharing, your calendar is a timeline, add rss + ical feeds, all data is
exportable, calendar badges + widgets, instant home page, track your buddies, custom webtop/start page, reliable messaging, tracked link sharing,
the best to do list ever."